Toner carrier and method of producing the same

Abstract

A method of producing a developing roller applicable to a developing device included in an image forming apparatus and capable of carrying a great amount of toner thereon by generating microfields. The surface of a conductive base is covered with a net constituting of conductive fibers and dielectric fibers woven together. The fibers are heated by a heater to melt with the result that conductive portions and dielectric portions appear on the surface of the developing roller.

What is claimed is: 
     
       1. A method of producing a toner carrier, comprising the steps of: (a) winding or wrapping a surface of a conductive base with conductive fibers and dielectric fibers such that the conductive fibers are interleaved in a criss-crossing pattern with the dielectric fibers; and   (b) heating said conductive fibers and said dielectric fibers to melt at least part of said conductive fibers and said dielectric fibers to thereby form a smooth surface on the toner carrier, whereby conductive portions and dielectric portions are formed and appear on the smooth surface of said toner carrier.   
     
     
       2. A method as claimed in claim 1, further comprising the step of (c) heating said conductive fibers and said dielectric fibers before covering said base, thereby removing a strain from said conductive fibers and said dielectric fibers. 
     
     
       3. A method as claimed in claim 1, further comprising the step of: fitting a contractile tube on said conductive fibers and said dielectric fibers before the step (b) of heating said conductive fibers and said dielectric fibers.   
     
     
       4. A method as claimed in claim 3, further comprising the step of heating said conductive fibers and said dielectric fibers before covering the surface of said base, thereby removing a strain from said conductive fibers and said dielectric fibers. 
     
     
       5. A method as claimed in claim 1, wherein the step of heating said conductive fibers and said dielectric fibers includes: pressing a heated heat roll against a surface of said conductive fibers and said dielectric fibers while rotating said heat roll to melt at least part of said conductive fibers and said dielectric fibers.   
     
     
       6. A method as claimed in claim 5, further comprising the step of (c) heating said conductive fibers and said dielectric fibers before covering the surface of said base, thereby removing a strain from said conductive fibers and said dielectric fibers. 
     
     
       7. A method of producing a toner carrier for carrying a toner thereon by forming closed electric fields, comprising the steps of: (a) winding or wrapping a surface of a conductive base with conductive fibers and dielectric fibers; and   (b) causing at least one of said conductive fibers and said dielectric fibers to melt, whereby said conductive fibers contact said conductive base while conductive portions and dielectric portions are formed on a surface of said toner carrier.   
     
     
       8. A method as claimed in claim 7, wherein said conductive fibers contain a conductive material, the melting in step (b) causing said conductive material to be dispersed only in said conductive portions. 
     
     
       9. A method as claimed in claim 7, wherein the step (b) comprises the steps of: (c) fitting a contractile tube on said conductive fibers and said electric fibers;   (d) heating said toner carrier at a temperature lower than a melting point or softening point of said contractile tube;   (e) cooling the surface of said toner carrier; and   (f) removing said contractile tube.   
     
     
       10. A method as claimed in claim 7, wherein the step (b) comprises the steps of: (c) causing a heat roller to contact the surface of said toner carrier covered with said conductive fibers and said dielectric fibers, and causing said heat roller to rotate relative to said surface; and   (d) smoothing said surface while causing said conductive fibers and said dielectric fibers to melt.   
     
     
       11. A method as claimed in claim 7, further comprising the step of (c) heating said conductive fibers and said dielectric fibers prior to step (a), thereby removing a strain from said conductive fibers and said dielectric fibers. 
     
     
       12. A method of producing a toner carrier, comprising the steps of: (a) winding or wrapping a surface of a conductive base with fibers having respective conductive portions and respective dielectric portions; and   (b) causing at least one of said conductive portions and said dielectric portions of said fibers to melt, whereby said conductive portions contact said conductive base while conductive portions and dielectric portions are formed on the surface of said toner carrier.   
     
     
       13. A method as claimed in claim 12, wherein said conductive portions contain a conductive material, the melting in step (b) causing said conductive material to be dispersed only in said conductive portions. 
     
     
       14. A method as claimed in claim 12, wherein step (b) comprises the steps of: (c) fitting a contractile tube on said fibers;   (d) heating said toner carrier at a temperature lower than a melting point or a softening point of said contractile tube;   (e) cooling the surface of said toner carrier; and   (f) removing said contractile tube.   
     
     
       15. A method as claimed in claim 13, wherein the step (b) comprises the steps of: (c) causing a heat roller to contact the surface of said toner carrier covered with said fibers, and causing said heat roller to rotate relative to said surface; and   (d) smoothing said surface while causing at least said conductive portions and said dielectric portions of said fibers to belt.   
     
     
       16. A method as claimed in claim 12, further comprising the step of (c) heating said fibers prior to step (a), thereby removing a strain from said fibers.